Coevolution: Genes, Culture, and Human Diversity

Rating:
Summary: This is a classic, but still completely up to date
Review: In humans, both genes and culture are containers of information passed from one generation to the next. Both genes and culture affect the phenotype, and therefore individual behavior. It follows that both genes are culture are subject to Darwinian selection. In addition, genes are part of the environment in which culture evolves, and culture is part of the environment in which genes evolve. Of course, the physical representation of genes and culture are very different. Genetic information is coded in DNA, while cultural information is coded in the synaptical structure of the brain. Moreover, Fisher's fundamental theorem, which says fitness tends to increase, is true for a single genetic locus, but not for a single culture locus, since agents can sustain an increase in a fitness-decreasing meme. Durham uses the term 'meme' for a unit of cultural inheritance. I think his defense of this is one of the strongest points in this great book. He shows that culture cannot be identified with phenotype or behavior. It follows that we must drop the term 'geno-phenotype'. In its place we can use the term 'geno-memotype.' Variants at a cultural locus are called allomemes by Durham. Good choice.

We have learned much about brain functioning, the role of emotions, autism and sociopathy, and human altruism since this book was published (1991), and Durham uses no math, which I always thought a necessary part of gene-culture coevolutionary theory. Neither of these is a drawback, and indeed the fact that he produces a brilliant model of coevolution without the usual mathematical tools is a true tour de force!

Durham provides extended analyses of Tibetian marriage patterns, lactose tolerance, sickle-cell anemia, and disease transmitted by cannibalism. These are standards of the trade now, but Durham's analysis are absolute gems, even if you know the literature on the topic.